We have presented first results of our Northern Hemisphere survey for roAp stars including photometric observations for 17 stars. One star (HD 122970) turned out to be a new roAp star, furthermore rapid oscillations for HD 99563 were confirmed.
Including all program stars from other surveys, a statistical analysis
of absolute magnitudes (using Hipparcos data) and galactic coordinates
has been made. The galactic distribution of roAp and noAp stars show no
significant differences whereas the absolute magnitudes and/or the
effective temperatures show systematic trends. Evidence is given that the
effective temperatures for roAp stars are systematically too high when
"standard'' calibrations for H
photometry are applied.
Absolute magnitudes from Hipparcos data for roAp stars establish them as
main sequence objects. Three objects are outside the 
Scuti instability
strip which points towards a different excitation mechanism of the two classes
of pulsating star. This is also suggested by new pulsation models.
The Austrian Fonds zur Förderung der wissenschaftlichen Forschung partially supported this work under grants S7303-AST and S7304-AST. APT observations were supported under grant S7301-AST to K. G. Strassmeier.
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